Drag-head for dredging machines



Dec. 12, 1933. M, M. CONDRON DRAG HEAD FOR DREDGING MACHINES Filed Dec. 31, 1932 O MQ INVENTOR, MM. CONDRON I TTORNEY 0 O 0 I I I I I 0 w Patented Dec. 12, 1933 1,939,989 DRAG-HEAD FOR DREDGING MACHINES Mark M. Condron, Memphis, Tenn.

Application December 31, 1932 Serial No. 649,723

Claims.

This invention relates to dredging machines, and especially to an improved drag-head for dredging machines.

One object of the invention is to provide adrag- 5 head which, by the mere forward movement on the earthen bottom of a body of water, will very efficiently cut and turn up portions of the earthen bottom and direct these portions intothe mouth of the casing or hollow end-section of the suction pipe, so that the inflowing water surrounds the thus-loosened portions of earth andcarries it along while causing it to disintegrate and prevent choking of the suction pipe.

A further object is to provide a drag-head with 16 independently rotatable setsor series of concavoconvex cutting discs properly arranged infthe mouth of the casing, for easily rolling over rocks, logs and other solid impediments that cannot be cut thereby; and thus prevent such impedi- 20 ments from impedingthe progress or forward movement of the drag-head, and also prevent breaking of the parts by the combined power and resistance acting on the drag-head, and also prevent such solid matter from being entangled or engaged with the cutters so as to hinder their efficient action on the earthen bottom.

A further object is to provide a cutter head with 40 lifts the loosened portions of earth,but also di-' rects these loosened portions inward'towards the median line and forward in the direction of the new or water being sucked through the suction.

tube of which the drag-head is the rearmost section. y

A further object is to provide a drag-head with cup-bearings, viz., bearings that are closed oh'all. sides except the side through which enters the specific journal that rotates therein, so that all other sides are impervious to water and other materials thatwould interfere with proper lubrication of the journals of the cuttingldiscs; also to provide the bearings with water-excluding packlngs; and to provide means to firmly but removably secure the bearings in their respective seats in such relation that they cannot be removed except while engaged with the respective journals, so that they shield their inner surfaces and their journals from contact with earthen particles, grit etc., when removed for sharpening the cutting discs, and when being replaced after being properly lubricated.

' A further object is to provide the drag-head casing with a hingedcover section which serves a dual function, viz., (1) to regulate the current of water entering the drag-head, and (2) to dislodge pieces of wood etc. that may be carried up on the edges ofv the rotary cutters or cutting discs.

A further object is to provide a thoroughly practical and eflicient draghead, while eliminating costly, unwieldy and obstructive gearings and driving connections such as shown in some of the prior patents on drag-heads.

' Otherobjects and important features are pointed out or implied'in the following details of description in connection with the accompanying drawing'in which:

Fig. 1 is a'top plan view of a drag-head constructed according to my invention, a part being broken away, and'parts being in horizontal section.

Fig. 2 is a left side elevation of the device shown in Fig. 1, a part being broken away, and a part being in section along the median line, viz;, the line 22 of Fig. 1.

Fig; 3 i sja fragmental detail, part of the frame or casing and a cup-bearing being in vertical section along theline 3-3 of Fig. l.

- Fig. 4 is a fragmental detail view, the section being along the line 4-4 of Fig. 1.

, Referring to this drawing in detail, in which similar reference numerals refer to similar parts in the several views, the invention is described in detail as follows:

A hollow casing 1 is formed witha securing flange 1a at its front end which is preferably of circular cross section so as to be properly joined to and united with a section of suction pipe, this casing also forming the rear end section of thesuction pipe of a dredge or dredging machine of the forwardly moving type by which marine channels are deepened and cleared. The rear end of this casing is substantially twice as wide as the front end, hence about twice as wide as its depth'or height, and is primarily, wideopen and unobstructed except for it's rearwardly and upwardly inclined floor-extensions or spaced tongues 1b and 10 for a purpose presently explained.

A strongand rigid shoe or wear plate 2" is 0 removably secured on the casing by means of bolts 3 and 7 with their respective nuts.

Rotary cutters or concavo-convex discs 4 are united with their axles 4a which are journalled in cup-bearings 5 and 6, the bearings 5 being secured in the central tongue 10 by bolts 7 and their nuts, while the bearings 6 are secured under shoulders 1d of the casing 1, by bolts 8 and their nuts. There are two of the axles 40., each having one end journalled in a bearing 5 and a bearing 6, and each axle has a set or seriesof the concavo-convex discs 4 thereon. Each cupbearing is fitted with a bushing 9 and with an excluding ring or gasket 10 which serves to keep out water and grit while also serving tokeep in the lubrication. At 11 are shown plugs that close the lubricating ducts through which may be introduced any kind of lubricating material; and it is within the scope of this invention to make the axles hollow so as to serve as storage chambers for reserve supplies of lubrication.

Each bearing is formed with an apertured securing ear through which the bolts '7 and 8 extend while also extending through apertures of the casing 1, the bolts 7 also extending through apertures of the shoe 2 and serving as aids in holding the shoe in place.

The bearings 5 are further forward than the bearings 6, so that the axles 4a have their inner ends further forward than their outer ends, and

by this arrangement, the front edges or sectors respect to those of the discs of therother set, so

that as the earthenbottom is'being cut, it is also being forced inward or laterally towards the median line, and at the same time being lifted and carried forward, so the lifted earth is entirely surrounded by water, and so that the forward motion minimizes the resistance against the inflowing water and thus minimizes the es- 'sential pumping power.

As seen in Fig. 2, the bottom' extensions or tongues 1b are upwardly and rearwardly inclined to a point near the respective axles 4a while being slightly spaced from theaxles and from the cutting discs 4, and these spaces or slots provide passages through which water flows inward (in consequence of the'suction pump,

not shown), while the tongues 11) serve .to aid the inflowing water by loosening the earth from the discs and helping to carry it forward.

'By removing the bolts 7 and 8, the bearings are freed from the casing, but remain in'en- 'gagement with the axles, being held by external air pressure because of being substantially airsealed by the'lubricated packings 10' and screw- -plugs;11; but when the plugs 11 are removed so that air can enter the bearings, the latter can be removed for replacing or repairing bushings or for other desired purposes. By thoroughly cleaning the exterior of the bearings and exposed adjuncts before removing the bearings, 'theiinterior thereof is kept free from detrimentalforeign matter.

'Any appropriate means may be employedjfor opening, closing or adjusting the door or hinged section 12, and it is within the scope of this invention to provide several of such doors or hinged sections which are independently operable or adjustable. It is also within the scope of this invention to place the hinges further forward and to extend the hinged section further rearward and downward than shown in the drawing. When dredging in deep and adhesive muck, it may be desirable to dilute the muck within the drag-head and conduit to prevent choking, and the door or doors 12 may be opened or adjusted so as to let in the desired quantity or proportion of water, above the muck-bed, for

inventive ideas as implied and claimed.- What I claim as my invention is:

1. In a drag-head for dredges, the combination of a hollow casing constituting the rear end section of a dredging suction pipe, the rear end of the casing being considerably wider than its height and than the front end, centrally and laterally disposed journal bearings in said rear end of the casing, the centrally disposed journal bearings being further forward than the laterally disposed journal bearings, axles journalled independently of one another in said journal bearings and having their inner ends further forward than their outer ends, and a set of cut- .110 ting discs for each axle, the lower sectors of the discs projecting below the bottom of the casing .while the rear sectors of the discs are inclined cutting discs having concave sides facing towards said median line, the front sectors of the .125 discs being substantially parallel with said median line and therefore parallel with the central line of travel of the drag-head in the operation of dredging.

3. The combination defined by claim 1, each of said lateral bearings being formed with an upwardly facing shoulder and an upwardly extending apertured ear, the rear lowerpart of the casing being provided with downwardly facing shoulders and with apertures'above the shoulders, and bolts removably secured in said openings and in the apertured ears while the upwardly facingshoulders are removably seated against said downwardly facing shoulders, said inner bearings being removably secured to the bottom of said casing in proper relation for providing a clear unobstructed passage thereover, whereby earth can be carried over the inner bearings into the casing, and' whereby the bearings and axles can be removed and replaced without separation from one another.

4.1The combination defined by claim 1, said Ycasing having a bottom which includes tongues that extend between the discs and areupwardly and rearwardly inclined and terminate atgpoints marily closed on all sides except the one open side into which the respective end of the axle extends, and each bearing being provided with a packing ring to cooperate with the closed sides for excluding water and other material.

MARK M. CONDRON. 

